This invention relates to sockets for use with fluorescent lamps, and, in particular, to a ballasted socket for a PL-type lighting fixture which is recessed in a building's ceiling.
Prior recessed ceiling fixtures have typically used incandescent bulbs. Although incandescent bulbs are effective for lighting rooms, they produce a considerable amount of heat. Fluorescent bulbs do not produce nearly as much heat as incandescent bulbs, and use less power than incandescent bulbs. In recent years, the lighting industry introduced compact fluorescent bulbs or lamps, sometimes referred to as PL bulbs or lamps. PL lamps are much smaller than traditional tube fluorescent lamps, and can burn as brightly as incandescent bulbs. However, lighting fixtures have generally been assembled with Edison-type sockets to accept incandescent bulbs. They thus do not accept a PL lamp. Consequently, PL lamps have been sold in conjunction with a ballast and adapter to enable to lamp to be screwed into the Edison-type socket which are common in older buildings. The PL lamp, with its ballast and adapter are sold as a unit. Thus, when the PL lamp breaks, or otherwise needs to be replaced, the ballast and adapter are replaced also.
Lighting fixtures designed to accept PL lamps are becoming more common, However, only a few sockets are commercially available which accept PL lamps. Those that do are complex t o assemble and often do not include the ballast or transformer necessary for the PL lamp. Consequently, the recessed sockets for such lighting assemblies include four wires, and a four-wire connector is required in the junction box to connect the lighting fixture to the ballasting system.